1. Field of the Invention
The present invention generally relates to an arrangement for clearing an optical surface of unwanted moisture and/or water adhering to and obscuring the surface, and more particularly, to such an arrangement where the optical surface is positioned remotely and generally out of reach.
2. Background of the Invention
Optical surfaces, such as, windows, transparent camera coverings, camera lenses, mirrors and the like, are oftentimes placed in locations not readily accessible for clearing. For example, on large trucks and buses, side-view mirrors and rear windows provide the only effective means for the driver to observe traffic to the rear of the vehicle, but they are difficult to reach for clearing while driving.
This is a problem when driving in inclement weather, because precipitation and moisture from the road can adhere to and obscure these optical surfaces making it difficult to see. Also, side-view mirrors and rear windows of buses are located high off of the ground, making it difficult to clean them when stopped. Moreover, during wet and rainy weather, the mirrors and rear windows need to be cleaned often so stopping to repeatedly wipe them is practical.
The use of cameras on vehicles is more prevalent now that video technology has become more affordable. For example, in addition to trucks, public transportation as well as school buses, and rental car shuttles routinely use cameras to obtain a rearward view to monitor the area behind the vehicle to make sure it is clear. These cameras can also be movable mounted so that the view can be selected and used as a surveillance camera inside or outside of the vehicle. Cameras exposed to the elements often have transparent covers to protect the camera lens from damage. During inclement weather, these covers or the camera lens itself can become covered with precipitation, water and moisture making it difficult to get a unclouded picture from the camera.
Similarly, security camera located outside are exposed to weather and over time, either the lens or transparent covering for the lens becomes soiled, making it difficult to get a clear picture. In addition, security cameras are often located at positions that are difficult to reach, such as, high on a pole or on a roof top of a building as well as inside the building on the ceiling or at an elevated position. This positioning makes it difficult for the camera lens or transparent cover to be reached for clearing.
In addition to the foregoing, optical surfaces associated with vehicle mirrors and cameras as well as security cameras are often moveable, making it even more difficult to clear effectively with an in situ device located at the optical surface because the optical surface do not stay in the same position.
There are known arrangements for clearing and clearing optical surfaces that use high velocity air flow, however, these known devices are expensive because they generally use a clearing solution in conjunction with the high velocity air flow and are inefficient since the air flow is directed upward over the optical surface and counter to the pull of gravity.
For example, U.S. Pat. Nos. 4,134,612 and 4,196,930 respectively disclose vehicle mirror clearing devices which use air flow deflectors to direct a stream of air across the face of the mirror and provide a clearing effect but these arrangements are generally ineffective since the force of the stream of air is limited by the vehicle's speed.
Accordingly, there is a need for a means by which remotely located, optical surfaces that are not easily accessible, such as, the back windows of buses, side-view mirrors of buses and trucks, cameras on large vehicles as well as security cameras located outside as well inside of buildings, can be easily and effectively cleared of grime and dirt as well as precipitation in a quick, easy, inexpensive and effective manner without the need for a person to reach the location of the optical surface and repeatedly manually wipe the surface to clear it of obscuring water droplets, moisture and/or precipitation on the optical surface.